Heretofore in the field of underwater surveillance, observation, and warfare, it has been desired to deploy a buoyant capsule into the water and maintain such capsule at a fixed depth therein. With this capsule maintaining observation or warfare equipment, the buoyant capsule may establish a station for surveillance or defense. Various means are available for deploying such a device; a submarine deploying it within the water, a ship deploying it from atop the water, and an aircraft deploying it from above the water. It is most desirable that the same type of device might be utilized regardless of the type of carrier from which it is deployed. It is further desirable that such a device may be deployed in water of unknown depth.
The devices hereinabove referred to are of such nature that the depth at which the buoyant capsule is ultimately maintained is critical. Consequently, with the buoyant capsule and weight assembly being deployed together, the separation between the two must commence at a predetermined level and the rate of separation between the two be effectively controlled to guarantee that when the weight assembly reaches the bottom of the water the buoyant member is maintained at the desired depth. Inherent problems exist with respect to assurances that the member connecting the buoyant capsule to the weight assembly not snap or experience excessive tension therein. Further problems are inherent when electronically controlled devices are utilized in that temperature compensation circuitry becomes necessary to overcome the detrimental effects of decreasing temperature with water depth. Further, the adverse effect that such low temperatures have on battery function and life lessen the reliability and functionability of the system as a whole.